EDIT: (130116) I don't mean it is complex or imaginary nor it is negative also, I tried hard to conceive it on the real line number (positive X-axis), by obvious means, a little idea came to me?, "every time you locate it between two digits, enlarge your number line say 10 times (in base 10 counting)", in order to locate it more clearly, after many finite digits I got tired, and also noticed that my number line is becoming longer than our milky way galaxy, then I simply realized I will never get it on our number line, because simply it is not there on our number line even at infinity?, it is a kind of distinct infinity that is not there?, it is simply an "illusion"
It is by definition $\pi$ is a ratio of circumstance to diameter of a circle, this was defined thousands of years back where the concept of numbers may had been restricted mainly on rational numbers, they could approximate it to few digits, and since then with the help of supercomputers nowadays it was approximated to many trillion digits, and we all know that $\pi$ never ends (being irrational number that is impossible to construct), it is always a ratio of two integers say $n/m$, where both $n$ & $m$ don't exist, then how can we consider it as a constant?
It is rather a non existing number on our real number line, because first it is impossible to construct (with rigorous proof), second there is no circle with exactly an integer diameter & integer circumstance (also this is proved rigorously), that doesn't necessarily imply its non existence or consistency in other "undefined" number line!?